The present invention relates to a CO2 abating latex coating composition, more particularly, a latex coating composition comprising polymer particles functionalized with acetoacetoxyethyl groups. Post film-forming curing of latex films is desirable to achieve improved hardness, as well as chemical-, scrub-, dirt-pickup-, and print resistance in the final coating. To that end, the use of polymeric binder particles functionalized with acetoacetoxyethyl methacrylate (AAEM) has been a mainstay for ambient cure of architectural coatings. AAEM has relatively low toxicity and undergoes oxidative and reacting crosslinking efficiently to provide an excellent balance of properties in the final coating.
But this favorable outcome comes with an undesired side effect: The reactive acetoacetoxy groups hydrolyze during latex storage to liberate carbon dioxide, thereby causing undesirable and potentially catastrophic pressure buildup within the storage vessel. This pressure buildup can be mitigated using ammonia but it too has its drawbacks: Ammonia imparts a strong odor and often causes yellowing in the final coating; moreover, formulators face ever-increasing regulatory pressure to remove ammonia and other volatile amines from their paint formulations. It has also been found that ammonia, which is thought to stabilize AAEM in the enamine form, does not actually prevent the formation of CO2. (J. Coat. Technol. Res., 10(6), 821-828, 2013). Accordingly, it would be desirable to find an economically feasible low VOC alternative for preparing a shelf-stable self-curing coating composition.